Mashup Macro - Fibonacci Number Generator

This Mashup Macro accepts a Fibonacci sequence number as input and then outputs the corresponding Fibonacci number.

The Incas used them.  They are over 3,000 years old.  Now you can get them from a simple Mashup Macro.  For those of you that want the whole story on Fibonacci numbers, I suggest you read up: http://en.wikipedia.org/wiki/Fibonacci_number

<macro name="fibonacci">
            <input name="seqNumber" type="number"/>
            <output name="fibNum" type="number"></output>
            <if condition="$seqNumber = 0">
                  <assign literal="0" outputvariable = "$fibNum"/>
            </if>
            <if condition="$seqNumber = 1">
                  <assign literal="1" outputvariable = "$fibNum"/>
            </if>
            <if condition="$seqNumber > 1">
                  <variable name="minus2" type="number" default="0"/>
                  <variable name="minus1" type="number" default="1"/>
                  <for variable="i" startcountervalue="1" finalcountervalue="$seqNumber - 1">
                        <assign fromexpr="$minus2 + $minus1" outputvariable="$fibNum"/>
                        <assign fromvariable="$minus1" outputvariable="$minus2"/>
                        <assign fromvariable="$fibNum" outputvariable="$minus1"/>
                  </for>
            </if>
       </macro>